Gonzales was the best player for 8 years. Laver was the best player in the world for 7 years. Hoad was considered unbeatable when he played his best tennis. Kramer revolutionised tennis, considerably widening the quality gap between the top professional players and the top amateur players from 1948 onwards. They are on a pedestal because they were that good.

Why don't we hear the same arguments for Federer, Nadal, Djokovic, and Murray? Why do people say the field is weak when these guys dominate but not when Gonzales, Laver, Rosewall and Hoad were dominating? I'm not arguing against the GOAT-ness of all of them. It's just that something has to give. You can't have it both ways. Besides, you and I both know that it was significantly easier winning a Major back then than it is now. Tennis is now more global, more professional, more competitive, and more athletic.

PS : The consideration that Hoad was unbeatable when he played his best Tennis is as meaningless as, "Nadal is unbeaten in the matches that he won."